robertson



(No Model.)

' 3 SheetsSheet l. J. ROBERTSON.

APPARATUS FOR MAKING TUBE BLANKS.

NIL 447,583.

Patented Mar. 3,1891.

INVEN U THE mums FETERS cm, wow-mum, w'snmumu n c (N0 M 3 SheetsSheet 2.

J.ROBERTS'ON. APPARATUS'FOR MAKING TUBE BLANKS.

Patented Mar. 3',- 1891.

WT E5 THE mama rga-rzns co., wow-map, msumcn'ou, m c,

3 Sheets-Sheet 3.

Patented Mar 3, 1891.

J-. ROBERTSON. APPARATUS FOR MAKING TUBE BLANKS.

(No Model.)

NHED STATES JAMES ROBERTSON, OF BIRMINGHAM, ENGLAND.

APPARATUS FOR MAKING TUBE-BLANKS.

SPECIFICATION forming part of Letters Patent No. 447,588, dated March 3, 1891.

Application filed March '7, 1890. Serial No. 348,032. (No model.) Patented in England April 4, 1888, No, 5,018 in France March a 13, 1839,No.196,678, and in Belgium March 14,1889,N- 85,583-

-To all whom it may concern.-

Be it known that I, JAMES ROBERTSON, a subject of the Queen of Great Britain and Ireland, and a resident of the city of Birmingham, in the county of Varwick, England, have invented certain new and useful Improvements in Apparatus for Making and Drawing Out Tubes from Tube-Blanks, (for which I have received Letters Patent in Great Britain, No. 5,018, dated April 4, 1888; in Belgium, No. 85,583, dated March 14, 1889, and in France, No.196,678, dated March 13, 1889,) of which the following is a specification, reference be ing had therein to the accompanying drawin gs. i

This invention relates to the manufacture of tubes of large diameter, such as are used for boiler-fines and like articles; and it consists in the improved method and apparatus hereinafter described, whereby ring-shaped billets or tube-blanks made externally of the desired diameter for the completed tubes are internally enlarged and longitudinally extended by rolling and elongating pressure applied to their interior surfaces, the tubular billet or blank being contained in a suitable tubular die and prevented from rotating while a mandrel provided with a series of rolls arranged to act on the inner surface of the blank is moved progressively through the blank and at the same time rotated therein, thus revolving the series of rolls about the axis of the mandrel. Means are provided for rotating said rolls on their own centers while they are revolving about their common center, and the rolls are arranged to reduce the thickness of the walls of the tube-blank by a combined outward and endwise pressure,

drel, and the construction of the die in which the tube is formed, all of which I will now proceed to describe and claim.

Of the accompanying drawings, forming a part of this specification,Figure 1 represents a side View of a mandrel embodying my invention. Fig. 2 represents a transverse section of the same on line 2 2, Fig. 1. Fig. 3 represents a longitudinal section on line 3 3, Fig. 2. Fig. t represents a side elevation, and Fig. 5 a top plan View, of the organized machine, including said mandrel, the die, and means for operating the mandrel and preventing rotation of the tube-blank. Fig. 6 represents an enlarged section on line 6 6, Fig. 5. Fig. 7 represents a top plan View of the parts of the machine shown in Fig. 6. Fig. 8 represents a section on line 8 8, Figs. 6 and 7 Fig. 9 represents a section on line 9 9, Figs. 6 and 7. Fig. 10 represents a section on line 10 10, Fig. 6. Fig. 11 represents an enlarged section on line 11 11, Fig. 5. Fig. 12 represents a top plan view of the parts of the machine shown in Fig. 11. Fig. 13 represents a section on line 13 13, Fig. 11, looking toward the right. Fig. 14 represents a section on line 14: 14, Fig. l1,looking toward the left. Fig. 15 represents a side elevation of the die and its operating devices. Fig. 16 represents a top plan view of the same. Fig. 17 represents an elevation from the left-hand end, as shown in Fig. 15, and Fig. 18 represents an elevation from the opposite end. Fig. 19 represents a section on line 19 19, Fig. 16.

The same letters of reference indicate the same parts in all of the figures.

A A represent the sections composing the die, the same being described in detail hereinafter. The die is suitably affixed to a rigid support, so that it is immovable when in operation. The internal or forming surface of the die is cylindrical and is of uniform diameter from end to end. The mandrel which cooperates with said die is provided with a series of rolls D which are the only portions of the mandrel that act directly on the tubeblank B inserted in the die. Said rolls are pi votally connected toa rotary head or holder composed of two parts or sections D and D, which are detachably connected by bolts a, Fig. 1, the pivotal connection between said head or holder and the rolls being shown in Fig. 3 as a series of studs 1), attached to the part D of the holder and entering sockets in the rolls. The rolls are arranged obliquely, as shown in Fig. 3,so thattheiroutersurfaces are inclined to the axis of the mandrel, their rear ends, which are preferably curved or rounded, being farther from said axis than their forward ends. The rolls are equidistant from the axial center of the mandrel, so that they bear simultaneously on the interior of the tube-blank. \Vhen the mandrel is 1'0- tated and at the same time moved progressively or endwise through the die, as hereinafter described, the rolls which are at the same time rotated independently on their own axis by contact with a positively-rotated central roll D are caused to move spirally through the tube-blank, the latter being in a hot viscid state, their inclined outer surfaces exerting an endwise rolling pressure on the metal of the blank, whereby so much of the metal as can lie between the outer portions of the rolls and the die is laid up and compacted against the walls of the die, and is thereby converted into a tube B Fig. 3, the surplus metal being at the same time displaced and forced forward by the action of the rolls until the entire blank has been internally enlarged and converted into a tube in the manner shown, the forward end of the blank being held during its displacement, to prevent the rotation of the blank, by a holding-up head G, Figs. 4, 5, 11, and 12, which retreats with the advance of the displaced portion of the blank, but is prevented from rotating, said head having teeth G which penetrate the end of the blank and engage it firmly with the head.

The head or holder D D is connected with a tubular shaft or stem-rod D, whereby said head or holder is rotated to revolve the rolls D about the axis of the mandrel. The rolls are rotated while they are thus revolved by contact with the central roll D", which is in rolling contact with the inner sides of the rolls D and is engaged with ashaft or stemrod D located within and extending through the tubular shaft D. The shafts D and D are rotated simultaneously in the same direction, but at different speeds, by means presently described, the relative speeds being preferably such that the inner shaft or stemrod D makes three rotations to one of the tubular shaft D. It will be seen that the rolls D are thus rotated on their own axes while they are being revolved about the axial center of the mandrel, the result being as above stated.

The head or holder D D is removably connected with the shaft D, that rotates it, by a clutch member D affixed to said shaft, and corresponding clutch-teeth formed on the part D and engaged with the clutch member D, as shown in Figs. 1 and S. The central roll D is in like manner removably connected to its shaft or stem-rod D by feat-hers D on said stem-rod entering grooves in .the socket in said roll. This construction permits the ready removal of the mandrel-via, the head or holder, with its rolls D and the central roll D from the operating-shafts D I), so that after the mand relhasbeen forced through the tube'blank it can be disconnected from said shafts to permit the withdrawal of the latter from the completed tube and the removal of the tube, the mandrel being afterward re-engaged with the shafts for another operation.

The progressive or endwise forward motion may be imparted to the mandrel by any suitable m eanssuch, for example, as a hydraulic ram J, Figs. 4, 5, 6, and 7, working in a cylinder I, to which water under pressure is ad mitted in any suitable way to impel the ram forward, or in the direction indicated by the arrow in Fig. 0.

To the forward end of the ram is attached a sliding cross-head Y, which is connected by rods Y Y with another cross-head Z Said cross-heads are provided with cars, which are fitted to slide in grooves Z in the fixed guides N N. The rear end of the tubular shaft or stem-rod D is journaled in a bearing in the forward cross-head Z. The rear end of the stem-rod D is journaled in a bearing in the rear cross-head Y, the latter being bored out to form a socket or cavity of larger diameter than said rod, and provided with a brass bush ing Y and a leather washer or packing Y and a cover or gland Y securing said bushing and packing, the said cavity being thus adapted to hold oil, water, or other liquid to cushion the inner end of the stem-rod D and support the end-th rust of the mandrel, which is exerted almost entirely on said rod. This hydraulic cushion or end bearing reduces the friction on the end of the rotating stem-rod D to the minimum, as will be readily seen, so that said rod can rotate freely and almost without friction in the cross-head Y, not-withstanding the end-thrust or pressure exerted upon it by the mandrel when the latter is in operation.

The liquid-receiving cavity is hermetically closed, so that the liquid cannot escape, and should be provided with a filling-channel and a screw-stopper therefor.

Z represents a driving-shaft, which is j ournaled in fixed bearings and is rotated by power applied in any suitable way. Said shaft passes through bush-bearings Y Y in the cross-heads Y and Z said bearings being adapted to slide upon the shaft, it being borne in mind that the crossheads move with the ram J along the shaft, the latter having no endwise movement.

Z and Z represent gears rigidly attached to each otheror formed in one piece and fitted to rotate with and move endwise upon the shaft Z, the said gears being provided with tongues which enter longitudinal grooves Z in the shaft, 30- that the gears which are located between the cross-heads Y and Z are necessarily rotated by the shaft, but are free to move along the same with the cross-heads. The gear Z meshes with a gear Z, which is affixed to the stem-rod D, and the gear Z" meshes with a gear Z which is attached to the tubular shaft or stem rod D. Rotary motion is imparted to the shafts or stem-rods D D through the said gears from the shaft Z. The gears Z Z and Z- 'Z are so proportioned as to give the stem-rods D and D different speeds, the stem-rod D being driven at a faster rate than the tubular stem-rod D, as already described. The gears Z" and Z are provided with flanges which engage the sides of the gears Z and Z, as shown in Fig. 6, and thereby cause the gears Z and Z to move endwise with the ram J and the stemrods D D and their gears Z Z.

The head G, that engages the forward end of the tube-blank and prevents the same from rotating is attached to a rod G, the rear portion of which works as a ram in a hydraulic cylinder P, the arrangement being such that a suitable degree of resisting pressure can be imparted to the head G to prevent the endwise pressure of the mandrel from forcing the entire body of the tube-blank through the die when the mandrel first commences to operate on the rear end of the blank and before a sufficientportion of the metal has been laid up and compressed against the walls of the die as the finished portion of the tube to prevent such bodily displacement. The hydraulic cylinder P may have a loaded safety-valve P Fig. 12, or other equivalent water-escape to afford a sufficient resisting pressure on the stem-rod G and head G to hold the tube-blank while the mandrel is first enteringit and preventonly such endwise movement of the forward end of the blank as may be due to the displacement of the metal after the forming action of the mandrel, above described, has commencd. After the mandrel has advanced sufficiently into the tube-blank to fairly start the forma tion of the tube the resistingpressure maybe relaxed by opening the safety-valve P so that the head G will thereafter move with the outer end of the tube-blank without exerting any particular resisting pressure upon it, the only effect of the head upon the tube-blank being then to prevent the latter from rotating, and this is accomplished by means of ears G on the ram R and longitudinal grooves P in the inner surface of the cylinder P, said grooves receiving the ears G and preventing the rotation of the ram within the cylinder.

I do not limit myself to the described by draulic motor for impelling the mandrel forward, nor to the described hydraulic means for-first exerting a resisting pressure on the head G and then relieving said pressure, and I Inayimpel the mandrel and apply resisting pressure temporarily by any other suitable means. It is obvious, moreover, that the means for preventing the head G from rotating may be variously modified without departing from the spirit of my invention.

The die, as before stated, is composed of two sections A A, which together constitute a cylinder, the division being lengthwise of the cylinder. The lower section A is provided with'suitable bases for attachment to a bed or support and has at one end two bosses A projecting from opposite sides, and supporting-links A which extend around said bosses and around bosses A formed on the upper die-section A, the bosses A being adapted to partially rotate within the links A and thus permit the upward swinging movement of the section A, as indicated by dotted lines in Fig. 15, the lugs A links A and lugs r constituting hinges whereby the die may be opened to permit the removal of the tube formed therein. The tube is caused to closely till the die by the forming operation above described. Hence the importance of the provision for opening the die is evident.

Under the forward ends of the fixed section A is a strong supporting-frame A to which are affixed vertical hydraulic cylinders A in containing vertical rams A, the upper ends of which are in contact with lugs A secured to the forward ends of the movable section. Upon the admission of water under pressure to the cylinders A the rams A are raised, and bearing on the lugs A raise the diesection A, as indicated by dotted lines in Fig. 15.. The escape of water from the cylinders A permits the section A to return to place by its own weight.

The section A is locked to the fixed cylinder A by means of two horizontal rams A proj ectin ginwardl y from horizontal hydraulic cyiindersA which are affixed to the frame A 10, in which are formed recesses having beveled upper sides j and horizontal lower sides k. W hen the rams A are forced inwardly by the admission of water'under pressure to the cylinders A the beveled surfaces j bear on correspondingly beveled flanges A formed on the edges of the upper die-section A, and press the latter firmly down upon the lower section, the horizontal surfaces 70 at the same time bearing on the horizontal under surfacesof flanges A on the fixed section A. The section A is therefore adapted to be securely held at its forward portion by the projection of the rams A from their cylinders and released by the retraction of said rams. The improved die, constructed and operated as described, may be used with any other mandrel adapted to act on the inferior of a ring-billet or tube-blank.

The operationis as follows: The die being opened, the ring-billet or tube-blank in a hot viscid state is placed within the die, and the latter is then closed and its sections secured together. The head G is moved forward to a bearing on the forward end of the Said rams have enlarged heads A Fig.

ITO

blank and the resisting pressure is applied to the stem-rod of said head. The mandrel is then advanced and rotated both bodily and as to its individual rolls, as described, and enters the blank, the rolls D acting on the inner surface of the blank, forming the tube 13 upon the walls of the die and forcing the surplus metal forward. The resisting pressure of the head G is maintained until the tube-forming operation has fairly commenced and then is (or may be) removed, as described, allowing the head G to move freely before-the advancing end of the blank, the head preventing the blank from rotating. \Vhen the mandrel has passed entirely through the die and has completed the tube, an orifice D, Fig. 3, in the center of the portion D of the mandrel, and another orifice D in the central roll D", receive a stud G on the forward end of the stem-rod G, the latter having at this time reached the end of its retreating movement, so that it is held stationary while the mandrel parts D and D" are moved upon it, said parts being thus supported by the stud G The stem-rods D and D are now withdrawn, the clutch D being thus separated from the part D of the mandrel, and the stem-rod D is withdrawn from the roll D". The mandrel is thus left on the stud G. The backward motion of the stem-rods is continued until said rods are entirely withdrawn from the die and the latter then opened and the completed tube removed. After this the mandrel is moved back through the die by advancing the stem-rod G and head G until the part D and the central roll D are respectively re-engaged with the stem-rods D and I), after which the head G is moved back through the die into position to support theadvancing end of the next blank inserted therein.

The hydraulic ram .T maybe retracted to withdraw the stem-rods I) D from the mandrel and die by means of a second ram L working in a hydraulic cylinder K and having at one end pulleys 4' 2' arranged in the bights of two chains 8 s, which are attached to a fixed support and to the cross-head Y.

The stem-rod G may be moved forward to carry the mandrel back to its starting position by a ram (-2 working in a hydraulic cylinder P and having a pulley 0* arranged in the bight of a chain 5, which is attached at one end to'a fixed support and at the other end to the head G.

I claim- 1. As an improvementin apparatus for making and drawing out tube-blanks, tubes, and tubular articles, the com bination of a die, a mandrel composed of a series of obliquelyarranged forming-rolls, a rotary head or holder therefor, whereby said rolls may be revolved about the axial center of the mandrel, and a central roll supporting said forming-rolls and having direct frictional contact therewith, means for revolving the series of formingrolls, and means for independently rotating the central supporting roll, as set forth.

2. The combination of a head or holder, a series of obliquely-arranged rolls journaled therein, a tubular shaft or stem to which said head or holder'is aflixed, and a central roller arranged to support and having direct frictional contact therewith, said series of rolls aflixed to a stem which is journaled in said tubular stem and is rotatable independently of the latter, as set forth.

3. The combination of a head or holder D, a series of rolls journaled therein, a tubular shaft or stem to which said head or holder is affixed, a central roller arranged to support said series of rolls and affixed to a stem which is journaled in said tubular stem, and mechanism for independently rotating said tubular stem and central roller-stem, as set forth.

4-. The combination of a rotary mandrel having a stem, as D, mechanism for rotating the san1e,a progressively-moving carrier whereby endwise motion is imparted to said mandrel while it is rotating, and a hydraulic back center supported by said carrier and receiving the rear end of said stem, said back center constituting an anti-friction support for the end-thrust of therotating mandrel, as set forth.

5, The combination of a rotary mandrel, mechanism for rotating the same, a hydraulic ram J, constituting a carrier, whereby the mandrel is moved endwise while rotating, and a hydraulic back centerattached to said ram and consisting of a head having a cavity receiving the stem of said mandrel and containing a liquid cushion to support the end-thrust of said stem, as set forth.

6. In a tube-forming machinehaving a mandrel composed of a series of forming-rolls, a rotary head or holder carrying said rolls, a tubular stem secured to said holder, and a central roll supporting said forming-rolls and having a stem journaled in the tubular stem, the combinatiomwith said mandrel. of gears on said stems, a positively-rotated shaft havin g gears rotatively engaged with but adapted to slide along said shaft, said sliding gears engaging the gears in the mand rel-stems, and means for imparting endwise movement to said mandrel while the parts thereof are retating, as set forth.

7. The combination of the mandrel having the outer and inner stems D D and the rolls supported thereby, gears Z Z, attached, respectively, to the stems D D, the gears Z' Z rotatively engaged with and adapted to slide on a positively-rotated shaft, ahydraulic ram arranged to impart endwise motion to the mandrel through the stem D, and a hydraulic back center attached to said ram and receiving the stem D, as set forth.

8. The combination of the mandrel having the outer and inner stems D D, the positively-rotated shaft Z, rotated in fixed bearings, the sliding bush or bracket Z, in which the stem D is journaled, the ram J, having the hydraulic back center Y, which receives the stem 1) and through the latter supports the end-thrust of the mandrel, the gears Z Z, attached, respectively, to the stems D D, and the gears .2 rotatively engaged with the shaft Z and adapted to slide thereon, said gears being engaged, as described, with the gears Z Z", whereby the endwise movement imparted to the mandrel by the ram J is imparted to the gears Z Z as set forth.

9. The combination, with the die and the rotating and progressively-moving mandrel having a series of forming-rolls operating, as described, within the die, of the yielding head G, adapted to bear on the inner end of the billet, and means whereby the rotation of the head G during its yielding movement is prevented, as set forth.

10. The combination, with the die and the rotating and progressively-moving mandrel having a series of forming-rolls, of the yielding head G, adapted to bear on one end of the tube-blank and provided with teeth to engage and prevent rotation of the blank, and means for preventing rotation of the head G during its endwise movement, as set forth.

11. The combination, with the die and the rotating and progressively-moving mandrel, of the yielding head arranged to bear on the inner end of the blank and hold the same from rotating, and means for applying retarding pressure to said head and releasing the head from said pressure, as set forth.

12. In a mandrel, the combination of the head or holder, the series of forming-rolls journaled therein, the tubular stem-rod having a clutch member engaged with clutchteeth on the head or holder, the central roll bearing on the forming-rolls, and the stemrod removably engaged with said central roll, whereby the said stem-rods may be withdrawn from the head or holder and central roll, as set forth.

13. The mandrel composed of the head or holder, the forming-rolls journaled therein, and the central roll bearing on the formingrolls, the stem-rods removably connected, respectively, with the head or holder and the central roll, whereby said stem-rods may be withdrawn from the mandrel, and a head G, provided withmeans for engaging and supporting the mandrel, and means for moving said head, whereby the mandrel may be returned to engagement with its stem-rods, as Set forth.

14. A tube-forming die composed of the fixed longitudinal sectionsAand the movable section A, connected at their inner ends by hinge members and provided with lugs or flanges at or near their opposite ends, fixed hydraulic cylinders N and rams therein, said ram bearing against projections on the movable sections, whereby the latter may be raised to open the die, as set forth.

15. A tube-forming die composed of the fixed longitudinal sections A and the movable section A, connected at their inner ends by hinge members and provided with lugs or flanges at or near their opposite ends, fixed hydraulic cylinders A and rams therein, said rams bearing against projections on the movable section, whereby the latter may be raised to open the die, and the fixed hydraulic cylinders A having rams which are formed to engage the lugs or flanges of the die-sections and lock the same together, as set forth.

16. The herein-described method of drawing out tubes from tube-blanks, the same consisting in applying outward and forward rotary pressure to the inner surface of a rigidlysupported blank, said pressure compacting and laying up a portion of the metal against the walls of the die in tube form and displacing a portion of the metal endwise of the die, as set forth.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, this 14th day of January, A. D. 1890. 7

JAMES ROBERTSON. WVitnesses:

XVILLIAn LINDSAY, WM. ROBERTSON. 

